Seoul: North and South Korea held fresh talks on Wednesday on reopening their joint industrial zone, with low hopes of an early agreement following months of friction. A fourth round of talks over the complex, a rare symbol of cooperation between the two rivals, took place just across the border in the North. Three previous attempts this month all ended in deadlock.

"The weather is not so bad today. Do you think we will have good results today?", the North's chief delegate Pak Chol-Su said at the start of the talks.

"I hope we'll be able to build a house that can stand against any gusts of wind or pouring rains", his South Korean counterpart Kim Ki-Woong replied, according to media pool report.

At a meeting earlier this month, the two sides agreed in principle to reopen the estate, where 53,000 North Koreans worked in 123 South-owned factories producing textiles or light industrial goods. But little progress has been made since then amid squabbles over which side will take responsibility for the suspension, and Pyongyang's refusal to accept Seoul's demand for firm safeguards against another unilateral shutdown.

Seoul also wants to allow foreign firms to operate in Kaesong in an apparent bid to make it more difficult for Pyongyang to shut the estate if relations worsen.

The North has called for an unconditional and quick restart, blaming Seoul's "hostile policy" for the suspension and the current deadlock in negotiations. "They kept talking past each other. These can hardly be called negotiations but deaf arguments," Chang Yong-Seok, senior researcher at the Institute for Peace and Unification at Seoul National University, said.

Professor Yang Moo-Jin of the University of North Korean Studies said the fourth and fifth rounds of talks would serve as a "watershed" in attempts to rescue Kaesong, the last remaining symbol of reconciliation.

The North needs to satisfy a US demand that it improve ties with Seoul before any talks with Washington. Seoul meanwhile will be seeking to cool tensions ahead of the military exercise, which if left unchecked could smother new President Park Geun-Hye's policy of measured trust building in its infancy, Yang said.

But, he added, "Both leaders of the two sides are taking a strong hands-on approach, meddling in the talks too intrusively, leaving their delegates little room to wiggle at negotiations."

Kaesong was the most high-profile casualty of the months of elevated tensions that followed the North's third nuclear test in February, the subsequent tightening of UN sanctions and US-South Korean military exercises.

Pyongyang last Wednesday proposed separate meetings to discuss the resumption of suspended cross-border tours to its scenic Mount Kumgang resort, and the reunion of families separated since the Korean War.

But it retracted its proposal a day later after Seoul only accepted the offer of talks on family reunions while refusing to discuss the Mount Kumgang tours -- another former valued source of hard currency for the impoverished communist state. The talks have been held at the estate in Kaesong, some 10 kilometres inside the North.

Many of the South Korean firms with factories in Kaesong, facing millions of dollars in damages due to the shutdown, have threatened to leave the complex permanently if the suspension continues.